packaging: Implement JDepsTask for jlink and jpackage

build-logic/packaging/src/main/kotlin/bisq/gradle/packaging/JDepsTask.kt

@@ -0,0 +1,82 @@
+package bisq.gradle.packaging
+
+import org.gradle.api.DefaultTask
+import org.gradle.api.file.DirectoryProperty
+import org.gradle.api.file.RegularFileProperty
+import org.gradle.api.tasks.InputDirectory
+import org.gradle.api.tasks.InputFile
+import org.gradle.api.tasks.OutputFile
+import org.gradle.api.tasks.TaskAction
+import java.io.BufferedReader
+import java.io.InputStreamReader
+import java.util.concurrent.Callable
+import java.util.concurrent.FutureTask
+import java.util.concurrent.TimeUnit
+
+
+abstract class JDepsTask : DefaultTask() {
+
+    @get:InputDirectory
+    abstract val jdkDirectory: DirectoryProperty
+
+    @get:InputDirectory
+    abstract val javaFxSdkDirectory: DirectoryProperty
+
+    @get:InputFile
+    abstract val jarFileToAnalyze: RegularFileProperty
+
+    @get:OutputFile
+    abstract val outputFile: RegularFileProperty
+
+    @TaskAction
+    fun run() {
+        val process = createAndRunJDepsProcess()
+        val futureTask: FutureTask<Set<String>> = createAndStartParseModulesNamesFutureTask(process)
+
+        process.waitFor(1, TimeUnit.MINUTES)
+        val moduleNames: Set<String> = futureTask.get(10, TimeUnit.SECONDS)
+
+        val concatenatedModuleNames = moduleNames.joinToString(separator = "\n")
+        outputFile.asFile.get().writeText(concatenatedModuleNames)
+    }
+
+    private fun createAndRunJDepsProcess(): Process {
+        val jDepsPath = jdkDirectory.asFile.get().toPath().resolve("bin").resolve("jdeps")
+        val javaFxSdkLibDirPath = javaFxSdkDirectory.asFile.get().toPath().resolve("lib")
+
+        val processBuilder = ProcessBuilder(
+                jDepsPath.toAbsolutePath().toString(),
+                "--module-path", javaFxSdkLibDirPath.toAbsolutePath().toString(),
+                "-s", jarFileToAnalyze.asFile.get().absolutePath
+        )
+
+        processBuilder.redirectErrorStream(true)
+        return processBuilder.start()
+    }
+
+    private fun createAndStartParseModulesNamesFutureTask(process: Process): FutureTask<Set<String>> {
+        val futureTask: FutureTask<Set<String>> = FutureTask(Callable { parseModuleNamesFromProcessOutput(process) })
+        val parseThread = Thread(futureTask)
+        parseThread.start()
+        return futureTask
+    }
+
+    private fun parseModuleNamesFromProcessOutput(process: Process): Set<String> {
+        val moduleNames = mutableSetOf<String>()
+
+        BufferedReader(InputStreamReader(process.inputStream)).use { reader ->
+            var line: String? = reader.readLine()
+
+            while (line != null) {
+                parseModuleNamesFromLine(line).forEach { moduleNames.add(it) }
+                line = reader.readLine()
+            }
+        }
+        return moduleNames
+    }
+
+    // Example: javafx.fxml -> java.base
+    private fun parseModuleNamesFromLine(line: String) =
+            line.split(" ")
+                    .filter { it != "->" }
+}